Gauge mechanism for grinding machines

ABSTRACT

This disclosure relates to automatic machines for grinding workpieces having axially spaced portions of different diameters, and particularly relates to a gauge mechanism which is used to determine the unground diameter of each workpiece portion to assure that the workpiece is within certain tolerances so that the grinding wheel may be advanced rapidly to a point just out of contact with the workpiece before reducing the rate of approach for the grinding feed. The gauge mechanism includes a workpieceengaging element or caliper of a chordal type having upper and lower shoe portions and a centrally located gauging probe member which is movable to cover a wide range of workpiece diameters. The work-engaging element is suspended by pivoted links of different lengths to permit the centerline of the probe to pass through or near the center of the workpiece, regardless of the workpiece diameter, so that each shoe portion will contact the work simultaneously.

United States Patent Primary Examiner Lester M. Swingle Attorney-Diller, Brown, Ramik & Holt ABSTRACT: This disclosure relates to automatic machines for grinding workpieces having axially spaced portions of different diameters, and particularly relates to a gauge mechanism which is used to determine the unground diameter of each workpiece portion to assure that the workpiece is within certain tolerances so that the grinding wheel may be advanced rapidly to a point just out of contact with the workpiece before reducing the rate of approach for the grinding feed. The gauge mechanism includes a workpiece-engaging element or caliper of a chordal type having upper and lower shoe portions and a centrally located gauging probe member which is movable to cover a wide range of workpiece diameters. The work-engaging element is suspended by pivoted links of different lengths to permit the centerline of the probe to pass through or near the center of the workpiece, regardless of the workpiece diameter, so that each shoe portion will contact the work simultaneously.

[72] Inventor Ralph E. Price Waynesboro, Pa. [21] Appl. No. 831,937 [22] Filed June 10, 1.969 [45] Patented Sept. 7, 1971 [73] Assignee Litton Industries, Inc.

Beverly Hills, Calif.

[54] GAUGE MECHANISM FOR GRINDING MACHINES 19 Claims, 9 Drawing Figs.

52 U.S. Cl 51/16531, 51/ 165.74 [51] Int. Cl B24b 49/04 [50] Field oISearch 51/165, 165.01,165.17,165.18,l65.04,165.09, 165.15, 165.20,165.21

[56] References Cited UNITED STATES PATENTS 2,603,043 7/1952 Bontemps 51/165 3,271,908 9/1966 Rocks 51/165 3,466,976 9/1969 Price 51/165 Pmmum um 3603044 SHEET 1 OF 5 27 P162. Y m

25 gs 0 I INVENTUR RALPH E. PFuCE A Q nrmuev's SHEET 2 OF 5 PATENIED s5? 1 WI ATTORNEYS GAUGE MECHANISM FOR GRINDING MACHINES This invention relates, in general, to new and useful improvements in a gauge mechanism for automatic machine tools, particularly grinding machines, and more particularly grinding machines which operate upon workpieces having axially spaced diameters of different sizes. The conventional method of controlling size on workpieces having multiple diameters is to provide either a visual indication or separate calipers preset for each diameter.

It is, therefore, an object of the present invention to provide an automatic gauge mechanism which is capable of measuring a relatively wide range of work diameters automatically in response to card coded information, and the gauge mechanism being operative for checking the unground dimension of each diameter of the workpiece prior to initiating a grinding cycle, or preventing the initiation of a grinding cycle if an unground dimension is outside preset card-coded tolerances.

A further object of this invention is to provide a novel linkage arrangement which maintains a geometric relationship between the gauge mechanism and the portion of the workpiece to be ground such that the probe axis is in a near horizontal line passing through or close to the centerline of the workpiece so that the upper and lower shoes of the gauge mechanism engage the workpiece with equal force, and with this geometric relationship being maintained for any unground dimension of the workpiece within the range of the machine and the gauge mechanism being used.

Another object of this invention is to provide means to automatically longitudinally position the gauge mechanism in line with the diameter to be ground to insure proper alignment of gauge shoes with the edge of the grinding wheel adjacent to a shoulder formed by a larger diameter of the workpiece.

A further object is to provide a gauge mechanism of the type heretofore described having upper and lower workpieceengaging surfaces of a caliper having a specific angle which will provide an eight to one ratio in amplification of an electrical gauge sensing element or probe to permit the measurement of a wide range of workpiece diameters.

Another object of this invention is to provide means to adjust the gauge mechanism vertically, horizontally, for roll and pitch movements, and for squareness with the workpiece to obtain an accurate gauge reading.

Another object of this invention is to provide means for automatically repositioning the gauge mechanism by spring pressure within air valves prior to the grinding operation to prevent the caliper from being affected by the force of coolant in a small space between the caliper and the shoulder formed by a larger diameter of the workpiece.

With the above and other objects in view that will hereinafter appear, the nature of the invention will be more clearly understood by reference to the following detailed description, the appended claimed subject matter, and the several views illustrated in the accompanying drawings.

IN THE DRAWINGS:

FIG. 1 is a front elevational view of a grinding machine, and illustrates the gauge mechanism positioned adjacent a large diameter portion of a multidiameter workpiece.

FIG. 2 is an end elevational view of the grinding machine of FIG. 1, and shows a chordal type caliper of the gauge mechanism in contact with the workpiece.

FIG. 3 is an enlarged fragmentary side elevational view of the gauge mechanism, and more particularly illustrates the linkage arrangement and actuating means for advancing the caliper against the workpiece with the axis of the probe in a near horizontal line close to or passing through the centerline of the workpiece so that upper and lower shoes of the gauge engage the workpiece with equal force.

FIG. 4 is a fragmentary end view of the gauge mechanism of FIG. 3 looking from right to left, and more clearly illustrates portions of the linkage arrangement.

FIG. 5 is an end view of the face of the gauge of FIGS. 3 and 4, and more clearly illustrates the details of the upper and lower shoes and the probe therebetween.

FIG. 6 is a fragmentary top plan view of a gauge mounting and locating mechanism, and the association thereof with a pair of switches forming a portion of the circuitry of FIG. 9.

FIG. 7 is a highly schematic view of the gauge mechanism, the mounting thereof, and a hydraulic system for imparting movement to the gauge mechanism incidental to a gauging operation.

FIG. 8 is an electrical circuit for controlling a grinding cycle of the grinding machine in accordance with the unground dimension of the work portion in position for grinding.

FIG. 9 is a schematic electronic circuit operable in cooperation with the gauging mechanism to control the grinding cycle if the dimension of the workpiece to be ground is within the specified unground dimension or tolerance.

Referring first to FIGS 1 and 2, a workpiece W having portions A through E of different diameters is mounted between a headstock I3 and a tailstock 14 of an automatic grinding machine 10 which is of a conventional construction and includes a bed 11.

The bed 11 has mounted thereon in a conventional manner for longitudinal sliding movement, a work carriage or support 12. The headstock 13 is mounted at one end of the support 12 and includes a suitable drive to rotate the workpiece W in a conventional manner. The tailstock 14 is mounted on the opposite end of the support 12, as is clearly illustrated in FIG. 1. The workpiece W is rotated by the headstock 13 about a predetermined axis and is shifted longitudinally with the support 12. For the purpose of illustration, longitudinal shifting of the support 12 may be effected by a hand wheel 15.

A punch card (not shown) housed in a conventional card reader 16 (FIG. 8) provides a signal to position the particular one portion which is to be ground longitudinally of the grinding wheel 17, as will be described more fully hereinafter. However, as the support 12 is shifted longitudinally a transducer 18, driven by the support 12, provides a signal when each portion of the workpiece is in the correct longitudinal position for grinding in alignment with the wheel 17. As shown in FIGS. 1 and 2, the portion A of the workpiece W is in alignment with the grinding wheel 17 and with a gauge mechanism of this invention which is generally designated by the reference numeral 20.

Reference is now made to FIGS. 3, 6, 7 and 9 which illustrate the manner in which the gauge mechanism 20 is supported adjacent the grinding wheel 17 for movement between the solid and phantom positions of FIG. 3. The gauging mechanism 20 is supported by a base member 21 which is secured to a table 22, the latter of which is best illustrated in FIGS. 3 and 6. The table 22 is in turn slidably mounted on a table slide 23 which is secured to a subbase 24. The subbase 24 is secured to a pedestal 25 which is mounted to the front of the bed 11, as is best illustrated in FIG. 1. The subbase 24 is adjustable to position the gauge mechanism for the maximum diameter to be ground which controls the transverse movement of a workpiece-engaging chordal-type caliper 26.

The base member 21 supports a gauge arm 27 which is pivotally mounted about a pivot 28. The lowering of the arm 27 moves the caliper 26 into a lower position which will permit the caliper 26 to be advanced against the workpiece diameter, as indicated in phantom outline in FIG. 7.

Movement of the arm 27 is effected by a piston rod 30 within a hydraulic motor 31 for raising or lowering the caliper 26. The hydraulic motor 31 is mounted within the base member 21, as best shown in FIGS. 3 and 7, and the piston rod 30 thereof is secured at 32 to an arm 33 which is in turn connected at pivot 28 to the lower end of the arm 27. A coil spring 34, which is best illustrated in FIG. 3, connects the base member 21 to an inner portion of the gauge arm 27 to provide means to raise the caliper 26 should a power failure occur during the grinding operation.

The arm 27 supports the caliper 26 by means of two arms 35, 36, the latter of which is longer than the former. The arms 35 and 36 are equally spaced along their lengths, but do not form a parallelogram because of the longer length of the arm 36 noted heretofore which provides near horizontal movement of the caliper 26 when a piston rod 37 within a hydraulic motor 38 is advanced to the right as viewed in FIGS. 3 and 7.

The caliper 26 is secured to a transducer housing 40 by screws 41 in a conventional manner, as is best shown in FIG. 3. The housing 40 is supported by vertical leaf springs 42 and 43 which are secured to support members 44 at opposite sides of the housing 40. The support members 44 are connected to the housing 40 through alignment rods 46 and 47 which are in threaded engagement with said members and lugs 48 and 49 which project from respected sides of the housing 40.

Reference is now made to FIGS. 6 and 7 which illustrate the manner in which the gauge mechanism 20 is controlled in response to a punch card to effect movement of the arm 27 and the caliper 26 carried thereby toward the workpiece W. The latter-mentioned means includes a piston 50 within a hydraulic cylinder 51, the latter of which is secured to the subbase 24 and includes a piston rod 52 which is secured to an extension (unnumbered) of the slidably mounted table 22 which carries the gauge base member 21.

Air valves 54 and 55 (FIG. 6) are secured to table brackets 56 and 57, respectively, so that movement of base member 21 to the right or left by movement of the piston rod 52 effects the closing of conventional pressure switches 3PS or 4P5 by reduced air pressure. Air valve 54 is open when the base 21 is positioned to the left as table slide 23 secured to the subbase 24 depresses a spring 60.

Air valve 55 is opened when the base 21 is positioned to the right by the slide 23 depressing a spring 61. The air valves 54 and 55 energize the pressure switches 3PS and 4P8 by reduced pressure in a conventional manner to provide a signal to permit the cycle to start when the base 21 and the caliper 26 are in the correct longitudinal position for measuring the unground portion of the workpiece W.

The upper ends of the leaf springs 42, 43 are secured to a lower swivel plate 63 which is secured to an upper swivel plate 64 by a threaded screw and swivel pin 65 (FIG. 3). The plate 64 is secured to the pivotal arms 35, 36 so that movement of the arm 27 by the motor 31 in the manner heretofore described or movement of the piston rod 37 effects movement of the caliper 26. Fine horizontal adjustment of the caliper 26 is obtained from an eccentric member 70 locked in the plate 63. Turning of the member 70 advances or retracts the caliper 26 a small amount as a notch 71 is provided in the housing 40 which is held against the eccentric member 70 by tension of the springs 42, 43.

Fine vertical adjustment of the caliper 26 may be made by adjusting a setscrew 75 (FIG. 2) to increase or restrict the forward movement of the arm 27 when the caliper 26 is lowered by the motor 31.

Adjustment of the alignment rods 46, 47 will permit any out of squareness to be corrected so that the side of caliper 26 is normal to the axis of the workpiece W.

Reference is now made to FIG. which illustrates more specifically the face of the caliper 26 which includes shoe portions 80 through 83 on the outer edges of the gauge which are ground to a dimension slightly under the center shoe portions 84, 85. This arrangement enables the outer shoe portions 80 through 83 to be used only for checking the longitudinal position of the workpiece while the center shoe portions contact the workpiece for positioning a probe 86 with its centerline passing through the workpiece axis or close thereto, as shown relative to two different diametered workpiece portions in FIG. 3. The outer shoe portions would contact a shoulder formed by a larger diameter when the workpiece W is not correctly positioned with comparison to the programmed location.

The shoes 84, 85 of the gauge contact the workpiece at points formed by a specific angle of l06, minutes and 36 seconds which provides an 8 to l ratio in amplification by the gauge sensing element or probe 86.

OPERATION The operation of the grinding machine 10 and particularly the gauge mechanism 20 will now be described with particular reference to the circuitry of FIGS. 7 through 9.

With the workpiece W placed in the machine and with a selector switch SS3 (FIG. 9) set in its closed automatic position, the carriage 12 automatically positions the left-hand portion A of the workpiece W in front of the grinding wheel 17 and the gauge mechanism 20 is positioned longitudinally in response to a programmed card in the card reader 16.

The gauge mechanism 20 is positioned to the left or right to align the caliper 26 with the side of the grinding wheel 17 adjacent the shoulder of a larger diameter portion of the workpiece W through a reset button (not shown) as part of the setup operation.

The gauge mechanism 20 is positioned to the left unless contact K6Y is closed from the card reader 16 as GAGE LEFT relay 7CR is energized through cycle selector switch SS3 and normally closed contacts 8CR1 and 30CR5. Upon the energization of the GAGE LEFT relay 7CR the contact 7CRl closes to energize a solenoid 4SOL (FIGS. 7 and 9) which shifts a valve 90 (FIG. 7) to the left. Hydraulic pressure is directed from a tank 91 by a pump 92 to the valve 90 through lines 93, 94 and 95. Pressure line 96 directs pressure from the valve 90 through a throttle valve 97 to the rod end of the hydraulic motor 51 (FIGS. 6 and 7). Piston 50 of the motor 51 is moved to the left which positions the base 21 and the caliper 26 in line with the left edge of the grinding wheel 17, at which point pressure switch 3PS (FIGS. 6 and 9) is closed by reduced pressure as the air valve 54 is opened in the manner heretofore described. The caliper 26 is positioned to the right when the GAGE RIGHT relay 8CR is energized through the selector switch SS3 when contact I(6Y is closed from the card reader 16 and normally closed contact 30CR6.

Contact 8CR2 closes to energize solenoid 5SOL and shifts the valve 90 (FIG. 7) to the right. Hydraulic pressure from the line through the valve 90 directs hydraulic pressure through a line 98 and through a throttle valve 100 therein to the head end of the cylinder 51.

Piston 50 is moved to the right to effect movement of the base 21 and the caliper 26 in the same direction until pressure switch 4P8 (FIGS. 6 and 9) is closed by reduced pressure as air valve 55 is opened.

The infeed lever 19 (FIG. 1) is moved to the advance position to condition the wheel support or wheel head 29 which carries the grinding wheel 17 for infeed movement during the cycle, after the diameter to be ground has been qualified.

Limit switch 4L5 is closed from said movement of infeed lever 19 to energize the WHEELHEAD-CONDITIONING relay 28CR (FIG. 9) causing contact 28CR1 to close thus providing a holding circuit for the relay 28CR through contact 35CR1 which is closed as the wheel head 29 is in its retracted position.

Contact 28CR2 closes to energize the CYCLE START relay 29CR through GAGE LEFT pressure switch 3PS or GAGE RIGHT pressure switch 4PS, one of which was closed by reduced pressure when the base member 21 and the caliper 26 were longitudinally positioned, in the manner heretofore described.

Contact 29CR1 closes in the circuit with INFEED relay 30CR.

Contact 29CR2 closes to energize the GAGE UP & DOWN relay 40CR to lower the caliper 26 through the mechanism heretofore described. Contact 40CR1 energizes solenoid 18SOL which shifts valve 102 (FIG. 7) to the left, wherein hydraulic pressure is directed from the pump 92 to said valve 102 through the lines 93, 94 and a line 103. A line 104 directs pressure from the valve 102 through a throttle valve 105 and a line 106 to the rod end of the hydraulic motor 31. This causes the piston rod 30 to move to the right, as viewed in FIG. 7, to pivot the arm 33 clockwise. Arm 27 likewise pivots clockwise and downwardly as piston rod 30 moves to the right, which lowers the caliper 26 to generally the phantom outline position shown in FIG. 7, although spaced leftward from the work- 1 piece W. Hydraulic fluid is discharged from the head end of cylinder 31 through line 87, throttle valve 88, line 89, valve 102 and return line 109 to the tank 91.

GAGE ON limit switch LS is closed when the caliper 26 is lowered to energize GAGE OFF relay 41CR.

Upon the energization of the GAGE OFF relay 41CR, the contact 41CR1 is closed which completes a circuit to energize GAGE ON & OFF relay 46CR through contact 35CR2 which was closed when the wheel head 29 was retracted.

Contact 46CR1 closes to provide a holding circuit for GAGE ON & OFF relay 46CR through contact 35CR2.

Contact 46CR2 closes to provide a holding circuit with GAGE ON & OFF relay 46CR through normally closed contact 36CR2 and contact 30CR4 which closes during rapid infeed.

Contact 46CR3 closes to energize GAGE ON & OFF solenoid 20801. which shifts a valve 107 to the left, as viewed in FIG. 7.

Hydraulic pressure is directed by the pump 92 to the valve 107 through lines 93 and 108, and a line 110 directs pressure to the head end of the hydraulic motor 38 which moves the piston rod 37 to the right, as again viewed in FIG. 7, which moves the caliper 26 toward and against the workpiece W in a near horizontal direction as the arms 35, 36 are pivoted. The prove or sensing element 86 is thus brought into contact with the workpiece W with its center line passing through or near the axis of the workpiece W, irrespective of the particular diameter thereof, as indicated by a second workpiece W in phantom outline in FIG. 3. This occurs because of the longer length of the arm 36 as compared to the arm 35 which brings the shoe portions 84, 85 into contact with the workpiece W at equal arcuate distance from the point of contact of the probe 86 against the workpiece W. At this time the gauge mechanism is in position to perform a qualifying function to determine the unground dimension of the workpiece in comparison to a preset dimension of the card in the card reader 16.

A conventional summing network 111 (FIG. 8) receives a signal from the probe 86 of the caliper 26, as well as a size signal from the card reader 16, which is converted from digital to analog form by a conventional converter 112. The output of the summing network is fed to a coarse meter 113 which produces a signal to indicate whether or not the portion to be ground is within the rough size tolerance for a particular diameter of the workpiece W which is to be ground. When the diameter to be ground is within the preset range established by the card in the card reader 16, the diameter is qualified or approved and a signal closes normally open contact QR (FIG. 9) to energize QUALIFICATION relay 48CR through normally closed contact 41CR2.

Contact 48CR1 closes to energize INFEED relay CR through normally closed WHEELHEAD OUT limit switch 6LS, contact 29CR1 and normally closed contact 50CR1 to effect further movement of the wheel head 29 and the grinding wheel 17 carried thereby toward the workpiece W to begin the grinding cycle.

Contact 30CR1 is closed to provide a holding circuit with INF EED relay 30CR. Contact 30CR2 is closed to energize IN- FEED solenoid 14SOL which advances the wheel head 29 and the grinding wheel 17 carried thereby.

Normally closed contacts 30CR5 and 30CR6 open to deenergize relay 7CR or 8CR and solenoid 4501.. or SSOL is deenergized which moves the GAGE SHIFT valve 90 (FIG. 7) to the inoperable or central position. Hydraulic pressure to the cylinder 51 is eliminated and the air valve 54 or 55 is reset by the springs 60 or 61, respectively, to reset said valve and to position the gauge mechanism 20, to provide clearance between the side of the shoulder and the side of the caliper 26 adjacent thereto.

The forward movement of the wheel head 29 opens wheel head BACK limit switch 8L8 which was held closed when the wheel head 29 was retracted against a solid stop by hydraulic pressure.

WHEELHEAD BACK relay 35CR is deenergized as the wheel head 29 is advanced.

Contact 35CR3 is opened which deenergizes GAGE ON relay 39CR and caliper 26 is retracted from the workpiece W.

If the dimension of the portion to be ground is oversize and outside the qualifying range indicated by the circuitry of FIG.

8, the gauge contact QR will not be closed and relay 48CR will not be energized. The wheel head 29 will therefore not be advanced as contact 48CR1 of the INFEED circuit will remain open.

If the dimension of the unground portion of the workpiece W to be ground is undersize, the caliper 26 provides a signal which is combined in the manner heretofore described with the signal from the card reader 16 and this comparison signal is received by a fine meter 125 (FIG. 8) which, in turn, produces a size signal to close contact SR to energize ON SIZE relay 50CR.

Normally closed contact 50CR1 is opened to prevent IN- FEED relay 30CR from being energized.

When the unground workpiece is at size or undersize, the wheel head 29 is not advanced as relay 48CR is never energized. Therefore, contact 48CR1 is never closed to energize INFEED relay 30CR except upon the closing of the contact OR in the manner heretofore described.

The operation of the feed mechanism, thus far described, is in keeping with that disclosed in commonly assigned US. Pat. Nos. 3,046,706 granted July 31, 1962, and 3,047,988 granted Aug. 7, 1962.

Caliper 26 is advanced during the grinding operation when a GAGE ON cam (not shown) on hand wheel 15 opens limit switch contact 9LS1. Relay 39CR is deenergized and reset by contact 35CR3 which closes when the wheel head 29 is retracted.

Limit switch contact 9LS2 is closed to complete a circuit to energize GAGE ON & OFF relay 46CR through contact 30CR4.

Contact 46CR2 closes to provide a holding circuit with GAGE ON & OFF relay 46CR through closed contacts 39CR4 and 30CR4. Contact 46CR3 is closed to energize solenoid 20SOL which shifts valve 107 to the left (FIG. 7).

Fluid pressure is then directed from the valve 107 to the head end of the cylinder 38 through the line 110 causing the piston rod 37 to advance to the right as viewed in FIG. 7 to again position the gauge 26 and the probe 86 onto the workpiece W.

During the remaining grinding operation the probe 86 sends a continuously changing signal corresponding to the change in the dimension of the workpiece W to the summing network 111. The specific construction of the probe 86 and a transducer associated therewith is fully disclosed in commonly assigned application Serial No. 824,433, filed May 14, 1969, in the name of Kurt M. Gabel.

The summing device also receives a signal from the card reader 16, as heretofore described, or from dial switches 127 representing the finished dimension of the particular workpiece portion being ground.

The progress of the grinding operation is shown on the coarse and fine meters 113, 125, respectively, which are arranged in series to visually show when the diameter is at finish size.

NEAR SIZE signal from the gauge mechanism 20 through the fine meter closes contact NSR to energize NEAR SIZE relay 49CR. A normally closed contact from relay 49CR opens to deenergize the increment feed, and spark out is then effected until ON SIZE contact SR is closed from the gauge mechanism 20 to energize relay 50CR. 7

Normally closed contact 50CR1 is opened which energizes relay 30CR to retract the grinding wheel 17 by retraction of wheel head 29.

The operation of the grinding machine 10 and the gauge mechanism associated therewith is continually repeated in the manner heretofore described until each of the workpiece portions A through E have been ground to size, or until such time that prior to grinding one of the portions a qualification signal is not received and the grinding operation is terminated by the prevention of wheel head 29 advancement.

It is also emphasized that the gauge mechanism 20 not only performs the qualifying function heretofore noted, but is also brought into operative relationship to the workpiece portion being ground toward the end of the grinding cycle and the shoes 80 through 85 thereof are subjected to wear, which if inproportionate, would result in inaccurate signals because of the shifting of the centerline of the probe 86 above or below the horizontal position shown in FIG. 3 and the absence of the centerline of the probe passing through or near the axis of the workpiece W. However, in order to equalize wear on the shoes the longer arm 36 of the arms 35, 36 permits the front portion of the caliper 26 to move through a flatter arc than the rear portion and at each end of its range of movement the centerline center of the workpiece W, irrespective of the particular portions A through E being ground. For the largest diameter portion being ground the axis of the probe 86 is perfectly horizontal and as intermediate and smaller diameter portions are ground, the centerline of the probe, through not horizontal, still passes through or close to the axis of the workpiece W due to the longer length of the arm 36 as compared to the arm 35 with the result that the upper and lower shoes 84, 85, respectively, engage the workpiece with equal force resulting in equal wear and accurate signals from the probe 86.

While preferred forms and arrangements of parts have been shown in illustrating the invention, it is to be clearly understood that various changes in details and arrangement of parts may be made without departing from the spirit and scope of this disclosure.

I claim:

In a grinding machine comprising,

a bed,

a work support on said bed having means for supporting a workpiece,

a grinding wheel support,

means for effecting relative transverse movement of said supports to begin grinding infeed,

. gauge means positionable to engage an unground portion of a workpiece and including means for generating an electrical size signal indicative of a proper unground dimension of a workpiece, and

. electrical circuit means for initiating said relative trans verse movement only upon receipt of said electrical size signal. The grinding machine as defined in claim 1 wherein said electrical circuit means includes relay means operable to initiate said relative transverse movement, and

switch means in the circuit of said relay means which is closed by said electrical size signal to energize said relay means to initiate said grinding infeed.

. The grinding machine as defined in claim 1 including means for generating a desired tolerance signal indicative of a desired unground dimension of the workpiece, and

. means for electrically comparing said desired tolerance feed operation to initiate the generation of said electrical size signal to thereby qualify the size of the diameter and the position of the workpiece prior to the infeed of the grinding wheel. The grinding machine as defined in claim 1 wherein a. said gauge means is a chordal-type caliper having a pair of angularly spaced arms to contact the workpiece at points formed by a specific angle to enable a predetermined range of workpiece diameters to be measured. 7. In a grinding machine, a. a bed,

b. a work support on said bed having means for supporting a workpiece,

c. a grinding wheel support,

(1. a grinding wheel rotatably mounted on said wheel supe. means to effect relative transverse and longitudinal movements between said supports,

f. a feed mechanism for effecting said transverse movement,

g. control means for actuating said feed mechanism to advance and retract said wheel support for a grinding operation,

h. a gauging device including means for engaging the workpiece,

i. means for supporting said gauging device comprising j. a pair of arms in spaced relation and pivotally connected to said gauging device,

k. a support member through which said arms are pivotally connected in spaced relation,

1. means for actuating said support member to shift said gauging device between operative and inoperative positions,

m. and a second actuating means operable only when said gauging device is in operative position for moving said gauging device into and out of engagement with said workpiece.

8. The grinding machine as defined in claim 7 including means for shifting said gauging device longitudinally of the workpiece through a distance corresponding to the width of said grinding wheel.

9. The grinding machine defined in claim 7 including means for shifting said gauging device longitudinally of the workpiece between the edges of said grinding wheel.

10. The grinding machine as defined in claim 7 including means for shifting said gauging device longitudinally of the workpiece between positions corresponding to the edges of said grinding wheel.

11. The grinding machine as defined in claim 7 wherein said arms are of different lengths, whereby the position of said gauging devices for any workpiece dimension within a specified range is such that the longitudinal centerline of said gauging device will intersect the axis of the workpiece.

12. The grinding machine as defined in claim 7 including a. means to control said feed mechanism,

b. said control means having a zone of operation between a specified dimension and a predetermined oversize,

c. said control means being responsive to workpiece dimensions only within said range to actuate said feed mechanism for a grinding operation.

13. The grinding machine defined in claim 7 wherein said arms are of different lengths, whereby the position of said gauging device for any workpiece dimension within a specified range is such that the longitudinal centerline of said gauging device will intersect the axis of the workpiece, and

a. the longer of said arms is positioned closer to the grinding wheel than the shorter of said arms.

14. The grinding machine as defined in claim 7 including a. means for resiliently suspendingly supporting said gauging device from said pair of arms.

15. The grinding machine as defined in claim 7 wherein a. said gauging device includes a pair of diverging workpiece-engaging arms, and

b. workpiece-size-detecting means between said workpieceengaging arms.

16. The grinding machine as defined in claim 8 wherein said shifting means includes a. said gauging device includes a chordal-type caliper having a pair of angular-1y spaced arms to contact the workpiece at points formed by a specific angle to enable a predetermined range of workpiece diameters to be measured.

19. The grinding machine as defined in claim 7 wherein a said gauging device includes a chordal-type caliper, and

b. said gauging device further includes means for adjusting said caliper horizontally, vertically and for squareness with the surface of the workpiece as well as to control roll and pitch to provide an accurate measurement of the various workpiece diameters. 

1. In a grinding machine comprising, a. a bed, b. a work support on said bed having means foR supporting a workpiece, c. a grinding wheel support, d. means for effecting relative transverse movement of said supports to begin grinding infeed, e. gauge means positionable to engage an unground portion of a workpiece and including means for generating an electrical size signal indicative of a proper unground dimension of a workpiece, and f. electrical circuit means for initiating said relative transverse movement only upon receipt of said electrical size signal.
 2. The grinding machine as defined in claim 1 wherein said electrical circuit means includes a. relay means operable to initiate said relative transverse movement, and b. switch means in the circuit of said relay means which is closed by said electrical size signal to energize said relay means to initiate said grinding infeed.
 2. The grinding machine as defined in claim 1 including a. means for generating a desired tolerance signal indicative of a desired unground dimension of the workpiece, and b. means for electrically comparing said desired tolerance signal with a signal from said gauge means to produce said electrical size signal.
 4. The grinding machine as defined in claim 2 including a. means for generating a desired tolerance signal indicative of a desired unground dimension of the workpiece, and b. means for electrically comparing said desired tolerance signal with a signal from said gauge means to produce said electrical size signal.
 5. The grinding machine as defined in claim 1 wherein a. said gauge means includes caliper means mounted for engagement with a workpiece portion in advance of the infeed operation to initiate the generation of said electrical size signal to thereby qualify the size of the diameter and the position of the workpiece prior to the infeed of the grinding wheel.
 6. The grinding machine as defined in claim 1 wherein a. said gauge means is a chordal-type caliper having a pair of angularly spaced arms to contact the workpiece at points formed by a specific angle to enable a predetermined range of workpiece diameters to be measured.
 7. In a grinding machine, a. a bed, b. a work support on said bed having means for supporting a workpiece, c. a grinding wheel support, d. a grinding wheel rotatably mounted on said wheel support, e. means to effect relative transverse and longitudinal movements between said supports, f. a feed mechanism for effecting said transverse movement, g. control means for actuating said feed mechanism to advance and retract said wheel support for a grinding operation, h. a gauging device including means for engaging the workpiece, i. means for supporting said gauging device comprising j. a pair of arms in spaced relation and pivotally connected to said gauging device, k. a support member through which said arms are pivotally connected in spaced relation, l. means for actuating said support member to shift said gauging device between operative and inoperative positions, m. and a second actuating means operable only when said gauging device is in operative position for moving said gauging device into and out of engagement with said workpiece.
 8. The grinding machine as defined in claim 7 including means for shifting said gauging device longitudinally of the workpiece through a distance corresponding to the width of said grinding wheel.
 9. The grinding machine defined in claim 7 including means for shifting said gauging device longitudinally of the workpiece between the edges of said grinding wheel.
 10. The grinding machine as defined in claim 7 including means for shifting said gauging device longitudinally of the workpiece between positions corresponding to the edges of said grinding wheel.
 11. The grinding machine as defined in claim 7 wherein said arms are of different lengths, whereby the position of said gauging devices for any workpiece dimension within a specified range is such that the longitudinal centerline Of said gauging device will intersect the axis of the workpiece.
 12. The grinding machine as defined in claim 7 including a. means to control said feed mechanism, b. said control means having a zone of operation between a specified dimension and a predetermined oversize, c. said control means being responsive to workpiece dimensions only within said range to actuate said feed mechanism for a grinding operation.
 13. The grinding machine defined in claim 7 wherein said arms are of different lengths, whereby the position of said gauging device for any workpiece dimension within a specified range is such that the longitudinal centerline of said gauging device will intersect the axis of the workpiece, and a. the longer of said arms is positioned closer to the grinding wheel than the shorter of said arms.
 14. The grinding machine as defined in claim 7 including a. means for resiliently suspendingly supporting said gauging device from said pair of arms.
 15. The grinding machine as defined in claim 7 wherein a. said gauging device includes a pair of diverging workpiece-engaging arms, and b. workpiece-size-detecting means between said workpiece-engaging arms.
 16. The grinding machine as defined in claim 8 wherein said shifting means includes a. slide means carrying said support member, and b. hydraulic means for shifting said slide means longitudinally of said workpiece as well as said support member and said gauging device carried thereby
 17. The grinding machine as defined in claim 7 wherein a. said gauging device includes caliper means mounted for engagement with a workpiece portion in advance of the transverse movement to qualify the size of the diameter and the position of the workpiece prior to infeed of the grinding wheel.
 18. The grinding machine as defined in claim 17 wherein a. said gauging device includes a chordal-type caliper having a pair of angularly spaced arms to contact the workpiece at points formed by a specific angle to enable a predetermined range of workpiece diameters to be measured.
 19. The grinding machine as defined in claim 7 wherein a. said gauging device includes a chordal-type caliper, and b. said gauging device further includes means for adjusting said caliper horizontally, vertically and for squareness with the surface of the workpiece as well as to control roll and pitch to provide an accurate measurement of the various workpiece diameters. 